1. Technical Field
This disclosure relates to light fixtures for controlled environments which include clean rooms, containment areas, surgical suites, and hazardous locations. The light fixture forms a seal between the controlled environment and the plenum environment and can be installed from below the ceiling of the controlled environment. The exemplary light fixture configurations are recessed within ceiling openings, seal to the lower surface of the ceiling structure, can be installed from below, and can support weight from above.
2. Background Information
Light fixtures for controlled environments such as clean rooms, containment rooms, surgical suites, and hazardous locations must be fabricated from inert materials, provide sealing functions, as well as providing desirable lighting properties. Controlled environment light fixtures are typically powered by an external power source and thus must provide a hermetically-sealed pathway for the power wires. The designers and users of controlled environments often want the light fixtures to be built into and recessed within the ceiling instead of hanging down from the ceiling support structures. These light fixtures must form a particulate and fluid impervious seal between the controlled environment and the plenum environment above the ceiling when the light fixture is installed. Standards and tests such as those defined by the National Sanitation Foundation protocols, the Medicines and Healthcare Products Regulatory Agency (MHRA) requirements, the National Environmental Balancing Bureau procedures must be met by components used in clean room construction.
The controlled environment can be located at any of a variety of facilities and the light fixture should be configurable for a variety of uses. For example, the light fixture may be used for applications such as pharmaceutical, biotech, biosafety, semi-conductor, surgical suite, and research facilities. The designers and users of these controlled environments desire light fixtures that can be configured with different light engines as well as providing a high quality, reliable seal. Different light distribution patterns are also desired for different applications. The light fixtures should be easy to install as well as being easy to maintain.